Understanding the Role of Nonionic Surfactants during Catalysis in Microemulsion Systems on the Example of Rhodium-Catalyzed Hydroformylation

Abstract

The application of microemulsion systems as switchable reaction media for the rhodium-catalyzed hydroformylation of 1-dodecene is being reported. The influence of temperature, phase behavior, and the selected nonionic surfactant on the reaction has been investigated. The results revealed that the structure and the hydrophilicity (degree of ethoxylation) of the applied surfactant can have a strong impact on the performance of the catalytic reaction in microemulsion systems, in particular on the reaction rate. The surfactant determines the boundary conditions for catalysis (interfacial area, local concentrations) and can also interact with the catalyst at the oil–water interface and hinder the reaction. In addition to the discussion of the experimental results, we present a proposal for the impact of surfactant-based reaction media on the reaction mechanism of the catalyst reaction.